The primary objectives of an instrument to remove portions of an ingrown toenail from a patient are to (1) depress soft tissue around the nail to expose the ingrown portion of the toenail, (2) remove the ingrown portion of the nail, and (3) remove the instrument without damage to the soft tissue. Instrument should be small so that it will not adversely impact the surrounding tissue or interfere with other portions of the body. It should also be light weight, rugged in construction, pleasing in appearance, easy to handle and manipulate during the precise nail removal process and low in cost.
Most of the current instruments may do one of these objectives well, but other objectives poorly or not at all. Common or specially adapted scissors and/or pliers type of instruments tend to pull the nail away from the soft tissue prior to cutting. Unless great care is exercised, this operation may cause injury to nail and soft tissue of the patient. This risk of injury is compounded since the soft tissue around the ingrown toenail may already be infected, injured and/or exceedingly sensitive. In addition, the small size of a scissors or pliers type of instrument adapted to ingrown toenail part removal requires a very skilled operator with steady hands in the best of circumstances.
Other prior approaches have been attempted to overcome the problems using tiny scissors and/or pliers in this application. One approach is an instrument to gently depress on the soft tissue to expose and file the ingrown toenail. This approach is illustrated in U.S. Pat. No. 2,479,514. Although this approach eliminates nail pulling and reduces the level of skill required, it requires extensive rubbing/filing action which may also injure the patient. Filing debris may also contaminate the injured or infected soft tissue areas.
Prior art safety knives (a protective surface proximate the cutting edge) have been used in pedicure and manicure applications, such as removal of exposed nails and corns on the hands or toes. These prior art safety knives could also be used for removal of ingrown toenails, once the ingrown nail portion is exposed from the soft tissue. These safety knives typically have a blade protective surface, spaced apart but opposite from the cutting blade. Related devices combine other pedicure devices (e.g., files and scissors) with a safety knife to trim, smooth or remove exposed items. These exposed nail and corn removal devices are illustrated in U.S. Pat. Nos.: Re 15,663; 1,219,626; 1,489,603; 1.002,377; 370,706; 843,602; 31,349. Other safety knife applications include surgical instruments, such as illustrated in U.S. Pat. Nos.: 1,763,939; 3,495,593; 1,015,472; and 3,013,553.
These prior art pedicure or manicure safety knife approaches have many limitations. These are primarily related to the need to gently depress and separate soft tissue away from the ingrown toenail prior to toenail part removal. The blade protective surface is not designed for this gentle depressing purpose, but to protect the blade and/or prevent the cutting blade from contacting other portions of the patient during cutting. These blade protective surfaces may break when exposed to the side loads caused by the unintended depressing the soft tissue or injure sensitive skin or other soft tissue. Proper separation of soft tissue from the ingrown toenail prior to cutting with prior art safety knives has required a separate depression/separation means to be used in conjunction with the safety blade to remove the ingrown nail portion.
Prior art safety blades and/or separate soft tissue depressors can also impair vision during the delicate nail portion removal operation. Good visibility is needed not only to perform the operation but to avoid further injury to infected or sensitive areas.
None of the prior art cited separates soft tissues from the ingrown nail portion to be removed and removes the nail portion without repeated movements. Visibility of the removal operation is also impaired in some of the prior art devices.
What is needed is a single device to separate and remove ingrown nail portions without repeated motions. This device should also provide good visibility and easy handling for the required precise depression, separation cutting and removal operations.